“Enron changed everything,” said Jordan Thomas, a former US Securities and Exchange Commission lawyer. “Because of how challenging the Enron fraud was, how document-intensive and time consuming, it . . . led to far more sophisticated accounting fraud teams at the SEC. It raised the bar for law enforcement.”

“It took 10 years for law enforcement to understand that the best way to fight financial fraud is to incentivise and protect whistleblowers,” said Mr Thomas, who helped draft that section of the Dodd-Frank Act and now heads the whistleblower practice at the Labaton Sucharow law firm.